Low profile furnace flue

ABSTRACT

A low profile flue for a furnace, including a chamber, a vent collar and a downdraft diverter. The chamber is disposed above the heat exchanger and receives exhaust gas therefrom, the chamber being defined by a bottom wall with an opening therethrough for receiving the gas, two side walls projecting upwardly from the bottom, a top wall extending between the sides and spaced above the bottom wall, and an upper wall with the vent opening therethrough. The upper wall is connected along a forward edge to the bottom wall, connected on opposite ends to the side walls, and connected at a rear edge to the top wall. The upper wall front edge is substantially aligned with one of the vertically oriented housing sides, and the upper wall extends from the front edge over the heat exchanger at an angle on the order of 45 degrees from horizontal. The vent collar is on the chamber upper wall about the vent opening. The downdraft diverter extends between the side walls inside the chamber adjacent the vent opening, and has a longitudinal axis substantially parallel to the chamber upper wall. A vent elbow has an inlet and an outlet oriented at an angle on the order of 45 degrees to each other, and is securable to the vent collar to selectively orient the outlet vertically or horizontally.

BACKGROUND OF THE INVENTION

[0001] The present invention is directed toward furnaces, and particularly toward a flue for venting hot gases from the furnace heat exchanger.

[0002] Furnaces are, of course, well known in the art for heating many different areas including homes and other buildings. Such furnaces are commonly located in an area which is preferably removed from the areas most frequently used by occupants in the heated area. For example, in homes having basements, the furnace is typically located in the basement generally away from commonly used living areas. In homes without a basement, the furnace is typically located in a small utility closet. In any case, however, it is preferable to minimize the space taken up by the furnace so as to otherwise maximize the usable areas in the building. Of course, the output of the furnace must also be distributed from the area in which the furnace is located, whether it be generated heat which must be distributed throughout the building or exhaust gas which must be discharged outside the building. Thus, the ability to minimize space taken up by the furnace is also restricted by not only the size of the furnace but also by the size and location of the related structure (such as heat distribution ducts and exhaust vents) which is required as well as the necessity to provide clear space around the furnace to allow access for servicing the furnace.

[0003] Further, furnaces are required to be installed in many different spaces and configurations, the details of which are oftentimes not recognized until the installation is underway. Therefore, furnaces in the prior art have often included parts which may be removed and replaced with different parts if necessary for a particular installation, which replacement is at times a relatively difficult and time consuming process even if done correctly. If an error is made in such a conversion, the resulting furnace installation could, beyond functioning at less than an ideal efficiency, present a dangerous condition. For example, if a furnace is converted from a horizontal exhaust vent to a vertical vent, incorrect assembly could result in excessive heat on some surface and/or dangerous leaking of exhaust gases.

[0004] The present invention addresses this long felt need to minimize the space taken up by furnaces, and further allows for simple installation which minimizes the possibility of incorrect assembly.

SUMMARY OF THE INVENTION

[0005] In one aspect of the invention, a low profile flue is provided for a furnace having a housing with generally vertically oriented sides enclosing a heat exchanger exhausting gas. The flue includes a chamber disposed above the heat exchanger and including a lower opening for receiving the gas and a vent collar on an upper wall above the heat exchanger. The upper wall includes a lower front edge extending from the front edge over the heat exchanger at an angle on the order of 45 degrees from horizontal. A downdraft diverter with a longitudinal axis substantially parallel to the chamber upper wall is inside the chamber adjacent the vent.

[0006] In one form of this aspect of the invention, the lower front edge is substantially aligned with one of the vertically oriented housing sides.

[0007] In another form of this aspect of the invention, the diverter comprises a pair of longitudinal members joined together along one edge at an angle to form a V-shape with the joined edges comprising the longitudinal axis. Both of the longitudinal members are oriented to taper away from the upper wall from the joined edges to divert downdraft through the vent collar away from the chamber lower opening.

[0008] In still another form of this aspect of the invention, a vent elbow is provided with an inlet and an outlet oriented at an angle on the order of 45 degrees to each other. The vent elbow inlet is securable to the vent collar to selectively orient the outlet vertically or horizontally.

[0009] In another aspect of the invention, a low profile flue is provided for a furnace, and includes a chamber, a vent collar and a downdraft diverter. The chamber is disposed above the heat exchanger and receives exhaust gas therefrom, the chamber being defined by a bottom wall with an opening therethrough for receiving the gas, two side walls projecting upwardly from the bottom, a top wall extending between the sides and spaced above the bottom wall, and an upper wall with the vent opening therethrough. The upper wall is connected along a forward edge to the bottom wall, connected on opposite ends to the side walls, and connected at a rear edge to the top wall, where the upper wall extends from the front edge over the heat exchanger at an angle on the order of 45 degrees from horizontal. The vent collar is on the chamber upper wall about the vent opening. The downdraft diverter extends between the side walls inside the chamber adjacent the vent opening, and has a longitudinal axis substantially parallel to the chamber upper wall.

[0010] In one form of this aspect of the invention, the upper wall front edge is substantially aligned with one of the vertically oriented housing sides.

[0011] In another form of this aspect of the invention, the diverter comprises a pair of longitudinal members joined together along one edge at an angle to form a V-shape with the joined edges comprising the longitudinal axis, both of the longitudinal members being oriented to taper away from the upper wall from the joined edges to divert downdraft through the vent collar away from the bottom wall opening.

[0012] In still another form of this aspect of the invention, a vent elbow is provided, and has an inlet and an outlet oriented at an angle on the order of 45 degrees to each other. The vent elbow inlet is securable to the vent collar to selectively orient the outlet vertically or horizontally.

[0013] In still another aspect of the present invention, a furnace is provided including a heat exchanger exhausting gas, a housing enclosing the heat exchanger, and a downdraft diverter. The housing includes generally vertically oriented sides and a chamber defined above the heat exchanger. The chamber includes a lower opening for receiving the gas and a vent collar on an upper wall. The upper wall includes a lower front edge which extends from the front edge over the heat exchanger at an angle on the order of 45 degrees from horizontal. The downdraft diverter is inside the chamber adjacent the vent, and has a longitudinal axis substantially parallel to the chamber upper wall.

[0014] In one form of this aspect of the invention, the upper wall includes a lower front edge substantially aligned with one of the vertically oriented housing sides.

[0015] In another form of this aspect of the invention, a vent elbow is provided having an inlet and an outlet on the order of 45 degrees to each other, with the vent elbow inlet being securable to the vent collar to selectively orient the outlet vertically or horizontally. The outlet may be substantially within a space defined by vertical planes defining the housing sides.

[0016] In still another form of this aspect of the invention, the outlet is above the chamber upper wall.

[0017] In yet still another form, the diverter comprises a pair of longitudinal members joined together along one edge at an angle to form a V-shape with the joined edges comprising the longitudinal axis, where both of the longitudinal members are oriented to taper away from the upper wall from the joined edges to divert downdraft through the vent collar away from the chamber lower opening.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a side view of a furnace and flue according to the present invention;

[0019]FIG. 2 is a perspective view of a flue incorporating the present invention, with one side surface cut away;

[0020]FIG. 3 is a side view of a flue according to the present invention as used with a horizontal vent;

[0021]FIG. 4 is a side view similar to FIG. 3, but with a vertical projecting vent; and

[0022]FIG. 5 is a side view similar to FIGS. 3-4, but with a horizontal lateral vent.

DETAILED DESCRIPTION OF THE INVENTION

[0023] A gas fired furnace 10 embodying the present invention is shown in FIG. 1. The furnace 10 includes a housing 12 defined by, inter alia, a plurality of vertically oriented sides (three of which, identified as 20, 22, 24, are shown in FIG. 1). A suitable heat exchanger 30 is suitably supported in the housing 12 to transfer heat between combustion gas and a fluid that is heated by the furnace, typically air. The heat exchanger 30 exhausts combustion gas in the direction of arrow 32 and into the flue 40 disclosed in greater detail below.

[0024] A pair of opposing sides of the housing 12 (e.g., sides 20 and 24, or side 22 and the side not seen at the rear of FIG. 1) may be open to allow suitable ducts (not shown) to be attached thereto so that fluid flow can be provided through the housing 12 and heat exchanger 30 for heat exchange purposes such as is known in the art.

[0025] It should be appreciated that virtually any furnace having a housing defined in an enclosed vertical space (i.e., with generally vertical sides) could advantageously use the present invention. Therefore, various furnace details relating, for example, to the heat exchanger structure, air flow, furnace control, etc., not specifically relevant to the flue 40 embodying the present invention are not disclosed herein. However, it should be appreciated that such various structural details could be readily and advantageously incorporated by a person of skill in the art once they have obtained an understanding of the invention disclosed herein.

[0026]FIG. 2 illustrates a flue 40 which incorporates the present invention. Specifically, the flue 40 includes a chamber 44 which is defined by a bottom wall 46, a top wall 48, two side walls 50, 52 (see FIG. 1), a rear opening 54, and an upper wall 56. The upper wall 56 is joined along a forward edge 59 to the bottom wall 46 at an orientation on the order of 45 degrees from horizontal. As best seen in FIG. 1, as oriented on the furnace 10 the flue 40 is positioned so that the forward edge 59 is substantially aligned with one of the sides 24 of the furnace housing 12.

[0027] It should be appreciated that while the forward edge 59 is illustrated as being the direct connection of the upper wall 56 and bottom wall 46, the connection could also be formed by use of a relatively small intermediate wall section between the upper and bottom walls 56, 46, which structure is intended herein to be encompassed by references to the upper and bottom walls 56, 46 being connected at the forward edge 59.

[0028] The bottom wall 46 includes an opening 58 therethrough for receiving the exhaust gas from the heat exchanger 30 disposed therebelow. The upper wall 56 includes a vent opening 60 therethrough with a collar 62 around the opening 60.

[0029] A downdraft diverter 70 is also secured in the flue chamber 44, supported at opposite ends on the side walls 50, 52. The diverter 70 includes a pair of longitudinal members 72, 74 joined together along an edge at an angle to form V-shape which generally extends in a horizontal longitudinal direction. The longitudinal members 72, 74 may be separate pieces joined together along the edge in a suitable manner, or could be a unitary piece bent generally along the middle to form the edge.

[0030] The joined edge of the diverter 70 is also generally oriented to be directly in line with the center of the vent opening 60 (i.e., a line extending through the center of the vent opening 60 and perpendicular to the plane of the upper wall 56 would generally intersect the joined edge of the diverter 70). In one suitable embodiment, the diverter 70 has its members 72, 74 joined together at an interior V-shape angle on the order of 135 degrees with each of the longitudinal members having a width on the order of two inches. The V-shape angle of the diverter 70 may also be oriented so that each member is at substantially an equal angle to the upper wall 56 (i.e., at an angle on the order of 22.5 degrees from the upper wall 56 where the diverter has an interior V-shape angle of 135 degrees such as previously described).

[0031] It should therefore be appreciated that the diverter 70 can divert any downdraft which might occur through the vent opening 60 (resulting, e.g., from the wind) and therefore assist in preventing poor combustion and flame disturbance which could result therefrom. Such downdraft is diverted back in the flue 40 to the rear opening 54.

[0032] FIGS. 3-5 help to illustrate the advantageous functionality of the flue 40 of the present invention as used on a furnace.

[0033] Specifically, it should be appreciated that the flue 40 can be used in a wide variety of installations, in which a vent elbow 80 with a forty-five degree bend can be selectively used to attach the vent collar 62 to a horizontal vent (FIG. 3) or a vertical vent (FIG. 4), or a ninety degree bend vent elbow 82 (FIG. 5) can be used to selectively attach the vent collar 62 to a horizontal vent extending in either direction laterally to the flue upper wall 56. As illustrated in FIGS. 3-5, the vent elbow 80 or 82 can therefore be oriented in a manner so that it does not substantially extend beyond the vertical plane defined by the furnace housing side (e.g., side 24 as shown in FIG. 1) with which the forward edge 59 of the flue 40 is substantially aligned. Thus, it should be appreciated that the furnace 10 can be used in confined spaces such as is commonly required while still allowing for proper connection to the exhaust gas vent and also allowing for clearance around the furnace both for safety and for access for servicing and the like. (It should be understood that while the elbows 80, 82 are illustrated in FIGS. 3-5 as including no portion extending beyond the furnace housing side 24, the advantages of the present invention could still be obtained to at least some degree even if the flue and elbow were connected with a portion of the elbow extending beyond the side 24.)

[0034] Further, it should be appreciated that the orientation of the upper wall 56 allows the vent opening 60 and collar 62 to be shaped as most commonly required (i.e., circular). Thus, as opposed to prior art structure in which space limitations required that the opening be made in a flattened oval, no adapter is required to convert between the collar and the vent, and therefore no space for such an adapter is required.

[0035] It should also be appreciated that in addition to the spatial advantages provided with a flue 40 incorporating the present invention, the structure further can provide significant manufacturing, installation and related safety advantages as well. For example, furnaces using the low profile flue of the present invention are particularly versatile, as they can be interchangeably used in a wide variety of installations without requiring complex adaptation between different installations. Therefore, installation may be easily and reliably accomplished, without potentially dangerous errors which could occur in prior art structures requiring complex adaptation from one environment in one installation to a different environment in another installation. Further, it should be appreciated that the diverter 70 can function advantageously as described no matter what the vent arrangement (e.g., vertical or horizontal venting), therefore also providing for ease of manufacturer since unique diverters are not required depending upon the vent arrangement.

[0036] Still other aspects, objects, and advantages of the present invention can be obtained from a study of the specification, the drawings, and the appended claims. It should be understood, however, that the present invention could be used in alternate forms where less than all of the objects and advantages of the present invention and preferred embodiment as described above would be obtained. 

1. A low profile flue for a furnace having a housing enclosing a heat exchanger exhausting gas, said housing including generally vertically oriented sides, comprising: a chamber disposed above said heat exchanger and receiving said gas therefrom, said chamber including a lower opening for receiving said gas and a vent collar on an upper wall above said heat exchanger, said upper wall including a lower front edge extending from said front edge over said heat exchanger at an angle on the order of 45 degrees from horizontal; and a downdraft diverter inside said chamber adjacent said vent, said diverter having a longitudinal axis substantially parallel to said chamber upper wall.
 2. The furnace flue of claim 1, wherein said lower front edge is substantially aligned with one of said vertically oriented housing sides.
 3. The furnace flue of claim 1, wherein said diverter comprises a pair of longitudinal members joined together along one edge at an angle to form a V-shape with said joined edges comprising said longitudinal axis, both of said longitudinal members being oriented to taper away from said upper wall from said joined edges to divert downdraft through said vent collar away from said chamber lower opening.
 4. The furnace flue of claim 1, further comprising a vent elbow having an inlet and an outlet oriented at an angle on the order of 45 degrees to each other, said vent elbow inlet securable to said vent collar to selectively orient said outlet vertically or horizontally.
 5. A low profile flue for a furnace having a housing enclosing a heat exchanger exhausting gas, said housing including generally vertically oriented sides, comprising: a chamber disposed above said heat exchanger and receiving said gas therefrom, said chamber defined by a bottom wall with an opening therethrough for receiving said gas, two side walls projecting upwardly from said bottom, a top wall extending between the sides and spaced above the bottom wall, and an upper wall with a vent opening therethrough, said upper wall being connected along a forward edge to said bottom wall, connected on opposite ends to said side walls, and connected at a rear edge to said top wall, wherein said upper wall extends from said front edge over said heat exchanger at an angle on the order of 45 degrees from horizontal; a vent collar on said upper wall about said vent opening; and a downdraft diverter extending between said side walls inside said chamber adjacent said vent opening, said diverter having a longitudinal axis substantially parallel to said chamber upper wall.
 6. The flue of claim 5, wherein said upper wall front edge is substantially aligned with one of said vertically oriented housing sides.
 7. The flue of claim 5, wherein said diverter comprises a pair of longitudinal members joined together along one edge at an angle to form a V-shape with said joined edges comprising said longitudinal axis, both of said longitudinal members being oriented to taper away from said upper wall from said joined edges to divert downdraft through said vent collar away from said bottom wall opening.
 8. The furnace flue of claim 5, further comprising a vent elbow having an inlet and an outlet oriented at an angle on the order of 45 degrees to each other, said vent elbow inlet securable to said vent collar to selectively orient said outlet vertically or horizontally.
 9. A furnace, comprising: a heat exchanger exhausting gas; a housing enclosing said heat exchanger, said housing including generally vertically oriented sides, and a chamber defined above said heat exchanger, said chamber including a lower opening for receiving said gas and a vent collar on an upper wall, said upper wall extending from said front edge over said heat exchanger at an angle on the order of 45 degrees from horizontal; and a downdraft diverter inside said chamber adjacent said vent, said diverter having a longitudinal axis substantially parallel to said chamber upper wall.
 10. The furnace of claim 9, wherein said upper wall includes a lower front edge substantially aligned with one of said vertically oriented housing sides.
 11. The furnace of claim 9, further comprising a vent elbow having an inlet and an outlet on the order of 45 degrees to each other, said vent elbow inlet securable to said vent collar to selectively orient said outlet vertically or horizontally.
 12. The furnace of claim 11, wherein said outlet is substantially within a space defined by vertical planes defining said sides.
 13. The furnace of claim 11, wherein said outlet is above said chamber upper wall.
 14. The furnace of claim 9, wherein said diverter comprises a pair of longitudinal members joined together along one edge at an angle to form a V-shape with said joined edges comprising said longitudinal axis, both of said longitudinal members being oriented to taper away from said upper wall from said joined edges to divert downdraft through said vent collar away from said chamber lower opening. 